Question about Digital Bypass feature of Harmon Kardon AVR 140

[Earwax]

Edited for more detail.

Question about the Harmon Kardon AVR 140 digital Bypass, the manual states on Analog bypass mode ( Sounds exactly the same as pure direct mode in Yamaha ? ) it directs the analog straight to the volume so it`s not specific what exactly this means.

Set up to accomplish this plug RCA cables in CD input slot, turn off tone control, select NO Surround mode so it`s true stereo and done.

What else is being implemented ? Is it simply just pure copper straight to the speakers ?

Another question: page 29 also states 5CH Stereo mode but I`m not sure if that also means a pure direct mode function...

Please consider I`m hoping for a very simplified response with as much detail as possible

If you need more specifics exact pages for PDF manual that assist in comprehending what the feature does Page`s 20- 21 then 28- 29.

https://support.harmankardon.com/on/demandware.static/-/Sites-masterCatalog_Harman/default/dw26d5dd8c/pdfs/AVR%20140%5EHK%5Eom%5E%5E%5E%5E.pdf

Thank you for your time !

 

[Mnyb]

All processing is digital so if you activate any processing analog signals has to go trough the ADC of the AVR to be converted to digital processed and back out trough the inbuilt DAC .

Bass processing is not only for the subwoofer as you remove bass from the other speakers and put trough the sub and also time align speakers and sub ( the distance settings ) .

So if you want processing it’s digital so subwoofer can not be used.

If your always using some kind of processing you migth as well connect most sources to a digital input of the AVR .

 

[Earwax]

All processing is digital so if you activate any processing analog signals has to go trough the ADC of the AVR to be converted to digital processed and back out trough the inbuilt DAC .

Bass processing is not only for the subwoofer as you remove bass from the other speakers and put trough the sub and also time align speakers and sub ( the distance settings ) .

So if you want processing it’s digital so subwoofer can not be used.

If your always using some kind of processing you migth as well connect most sources to a digital input of the AVR .

Thank you for the reply, I edited my question with more detail and fixed my mistake about the 5CH mode It was meant to be stereo not theater.

 

[AnalogSteph]

What else is being implemented ? Is it simply just pure copper straight to the speakers ?

Input selector --> digitally controlled volume (PGA) --> power amp --> protection relay --> speakers, usually.

Historically H/K AVRs tended to be a bit on the hissy side, but given this model's relatively modest 40 wpc power and 100 dB(A) SNR spec I'd be reasonably confident that this one ought to be decently well-mannered in this respect.

Another question: page 29 also states 5CH Stereo mode but I`m not sure if that also means a pure direct mode function...

Could be, not sure. It's a function that's trivially easy to implement in the digital domain, but could be done the old-fashioned way as well. One would have to study the service manual to be sure.

 

[Earwax]

Thanks for the details, How clean of a pure direct mode is it in comparison and would one with more years experience and education be able to notice a difference using same speakers ?

Yes very well mannered I`m highly impressed. Just need to have someone use REW to tune my setup as that program looks like it would take very much time for me to learn more time and frustration than I have available at this moment in time of 2025.........

Any recommendations I`m in Vancouver area ( Coquitlam ) of BC Canada...

 

[Chrispy]

5ch stereo isn't a direct or pure mode, but involves rerouting of the L/R channel to both mains and surrounds plus summing it for the center.

Using pure direct is when you want to listen to a source as provided rather than with any processing involved.

 

[phofman]

Direct quote from AVR140 service manual:

 

[DJBonoBobo]

The name is Harman, not Harmon.

 

[Earwax]

Direct quote from AVR140 service manual:

View attachment 437665

Thank you for the quote, funny I read it many times and was unsure just how accurate the wording was compared to the system sound itself as many companies imply very much without factually back it up.

I can honestly say from my well deciplined mindset, patient nature using just my ears
The wording used appears to be accurate and Pure.

 

[Earwax]

Input selector --> digitally controlled volume (PGA) --> power amp --> protection relay --> speakers, usually.

Thank you for taking the time to reply.

Can you explain how this is different from discrete amps ?

I have a very slight static noise in my tweeters at -40 db so a low midnight volume level. Nothing plugged in Nothing on pause...


The volume control starts at -80 db to +10 db but it appears to me completely unrealistic-60 db your ear has to be against the speaker...

 

[DVDdoug]

The volume control starts at -80 db to +10 db but it appears to me completely unrealistic-60 db your ear has to be against the speaker...

Are you sure those are decibels? Or maybe just numbers like a volume control marked 0-10? In any case, it's attenuation or gain. It's not a dB meter showing the level or loudness.

Although there is a direct correlation between digital and electrical dB levels, there is no standard calibration.

dB SPL levels (acoustic loudness in the air) is positive with 0dB approximately the quietest sound that humans can hear. It depends on the signal level, the gain of the amplifier, the sensitivity of your speakers, how close you are to the speakers, etc.

Electrical and digital audio dB levels are usually negative. With integer digital (like CDs or regular WAV files) 0dBFS zero decibels full scale is the "digital maximum". It's the highest you can "count to" with a given number of bits. There are floating point digital formats that can go positive (with virtually no limits) but your DAC is integer and limited to 0dB. When you play a file, the data is scaled to match the bit depth of the DAC so a 24-bit file isn't louder than an 8-bit file.

The correlation means that if you reduce the digital or electrical level by 3dB (usually more negative) the SPL level also goes down by 3dB, etc.

 

[Earwax]

Are you sure those are decibels? Or maybe just numbers like a volume control marked 0-10? In any case, it's attenuation or gain. It's not a dB meter showing the level or loudness.

They are the digital LED display volume control ( example -40 db ) guessing it`s just fluff marketing ?

 

[Earwax]

Spec`s from manual of AVR 140

Audio Section Stereo Mode Continuous Average Power (FTC)50 Watts per channel, 20Hz–20kHz,@ <0.07% THD,

Both channels driven into 8 ohms Six-Channel Surround Modes Power per Individual Channel Front L&R channels:40 Watts per channel@ <0.07% THD, 20Hz–20kHz into 8 ohms Center channel:40 Watts @ <0.07% THD, 20Hz–20kHz into 8 ohms Surround (L & R Side, Back) channels:40 Watts per channel@ <0.07% THD, 20Hz–20kHz into 8 ohms.

Input sensitivity/Impedance Linear (High-Level) 200mV/47k ohms Signal-to-Noise Ratio (IHF-A) 100dBSurround System Adjacent Channel Separation Pro Logic I/II 40dBDolby Digital (AC-3) 55dBDTS 55dBFrequency Response@ 1W (+0dB, –3dB) 10Hz –130kHzHigh Instantaneous Current Capability (HCC) ±25 Amps Transient Intermodulation Distortion (TIM) Unmeasurable Slew Rate 40V/µsec

 

[Earwax]

I`m trying to research if an amp like the Topping PA 5ii would be any clearer then my AVR 140 in pure direct mode using a simple SMSL - SU1 DAC as a pre amp.

Any assistance would be much appreciated, I`m enjoying the new research arena but as you are all well aware of it`s a bit overwhelming researching audio equipment upgrades, my gifts are related to healthy eating and disease prevention on a level of explanation that anyone can comprehend.

It appears as a close call ?

Thank you for your time,

Your Friend, a oppressed Canadian :]


My speakers listed here : JBL N28

Product Review

AVR 140 manual here:

https://support.harmankardon.com/on/demandware.static/-/Sites-masterCatalog_Harman/default/dw26d5dd8c/pdfs/AVR%20140%5EHK%5Eom%5E%5E%5E%5E.pdf

 

[Earwax]

Topping PA5 II Stereo Amplifier Review

This is a review and detailed measurements of the Topping PA5 II stereo balanced amplifier. It was sent to me by the company and costs US $219 (sale). There is a plus version with higher current power supply for $289.50. The fonts are hard to see but there is not much to read anyway. A power...

www.audiosciencereview.com

 

[Earwax]

One final question the AVR 140 appears to have better THD than the PA5 ii ?

My AVR 140 is showing 50W x 2 @8Ω THD <0.07%

PA5 ii spec 65W × 2 @8Ω THD+N<1%

• A THD level of 0.01% is considered very good and likely imperceptible ?
  
  
• A THD level of 0.1% is considered reasonably high distortion and may be noticeable ?
  
  
• A THD level of 1% is considered the point where distortion becomes noticeable ?

• Audibility Threshold:
  THD+N is considered inaudible when its level is below 0 dB SPL, meaning the distortion is below the level of the original signal.
  
  
• Examples:
  • If THD+N is -120 dB, it means the distortion is 120 dB lower than the original signal, making it virtually inaudible ?
    
    
  • At 1% THD+N, the distortion is only 40 dB lower than the music, making it easily audible ?

 

[phofman]

HK AVRx40's were designed quite nicely.

 

[livinon2wheels]

I always like H-K equipment, solid design, and decently built. Long term keepers usually. If you are satisfied with the power level and the feature set included in the piece you have there is little reason to 'upgrade' to something that is largely an unknown. This is setting aside 'upgrade-itis' and if you have been infected with that virus there is little I can say to dissuade you from spending your money...many of the new equipment featuring HDMI and modern interface features are so buggy that you will wish you had the H-K back. Be careful what you wish for.

 

[Earwax]

Thank for the feedback, my led display acts up sometimes turning off. I usually have it off anyway.

It also has OSD display on my TV if needed.


I'm very satisfied this unit, only curious as I did a speaker placement adjustment so now I'm not using center and rear channels only fronts sometimes with my 10 inch sub but only for movies...

I'm really just thinking ahead.

I'll probably just have the AVR repaired if anything else arises it's beautiful sounding in pure direct mode and want to keep it around regardless. Unless repairs are too high then I'll try to do it myself in spare time....

 

[Earwax]

Can I use a computer fan outside the housing to pull hot air out or push air through ?

I have a Noctua NF-P14s redux-1200 PWM, Quiet Fan, 4-Pin, 1200 RPM (140mm, Grey)

That is whisper quiet I wired it to usb to 12 volt adapter but stopped using it due to lacking knowledge about static charges In amps..